Door operating fluid motor system



Oct. 18, 1949. J. R. ALMOND DooR OPERATING FLUID MoToR -sYsTEM Filed bot. 24, 1945 ATTORNEY.

Patented Oct. 18, 1949 DOOR OPERATING FLUID MOTOR SYSTEM `lohn R.'.Almond, Cleveland, Ohio, assignor to The Midland. Steel v Products Company, Cleveland, Ohio, aA corporation of Ohio Application October 24, 1945, Serial No. 624,133

6 Claims. l

This invention relates to" door operating iiuid motor systems and mechanism, andan important object of the inventionisI to provide in such a system, an emergencypassenger `valve'whereby a passenger may, in an emergency, operate the system to open. the bus doors-in amanner that the operator cannot thereafter. close the doors from his station'until the passenger valve is returned to its normal.- position which will Cause automatic closing of the bus doors and return of the system tothe controlof the operator at his control station.

In cases of emergencies,.a,s when the bus operator is not in control of thebus and it becomes necessary for passengers to leave or escape from the same, the system provides an emergency valve which the passenger can operate at a point near the' doors to open. thesame independently of any action of the operator; the arrangement being such thatlthe emergency valve must be returnedto its normal position before the doors can again be closed or operated from the operators station, therebyv assur-- ing that the bus doors will not be operateduntil the bus driver walks to a point adjacent the doors and sees thateverything-is.in'order before resetting the emergency valve so thatA the doors can then be closed'by the operator andthe bus safely moved.

Another object of theinvention'is to; providea A simple double check valve andaJ threeor fourway emergency and manually operated valve which can be readily installed in a standarddoor operating system with only the additionfof a very small amount of pipi-ng. tothe Vregular system.

Other objectsand advantages ofthe invention will become apparent during the course of the following description.

ln the accompanying drawing,` forming a part of the application and whereinlike numerals` designate like parts throughout the several views, the single gure represents. a more or. less diagrammatic showing ofV the system, with the valves and part of the door engine in-section.

Referring now more particularly` to vthis-drawing, the numeral I designates a door engine cylinder in which a double actingpiston .2 .is reciprocated at an operatorswill by av fluid medium lower than atmospheric pressure, .butLiirthe'lprese ent illustration of the invention,l.it willbe. dea scribed as being air underv pressure or pressurei higher than atmospheric. The'right-.handz end:

of a cylinder is capped with al closurehead1, 5:.

having a pipe coupling 6. and the usualpressure; regulating valve l which. controlsthezinlet and: outlet of fluid medium to and. from the.. cylinder' to control the speed of-.movementoft-hefdoon'op.-- erating piston, as is wellunderstoodin the.' art... This closure head 5. has ani elongatedsbearingffe through which the piston.l rod-v 4. reciprocatesa.. This end of a door. engine .'willbe calledxthe; donn closing end of the cylinder since fluidimediumz entering the same will causer the pistonptomove.l

to the left oi the Figure toV closethehusdoorsa The opposite end of the cylinder.'isclosedeby;y closure plate 9 similar to the closure plate: 51;/ and having a pipe coupling Ill. and..pressure reg-:-a ulating valve Il associated therewith; Thissend of the door engine-Will be. called the doorxopen-- ing end since admission of the luidmediumi under pressure thereto will cause the'piston-...Zltof move toward the right of the Figure. to cause.l opening movement of the bus doors.

In order to direct the fluid medium to eitheri end. of the door engine, and: to exhaust` therefrom,.a control valve I2 is provided adjacentther drivers seat or control station in the bus. This.. is a four-Way control valve of thesnap action. type disclosed in my previous Patent No.-.2,243,937. granted June 3, 1941. This` valve isconnected.. tothe reservoir by a pipe I3 which suppliesfluid. medium under pressure to. a common inlet: i4.. having a pair of valvesea-tsland. I6 provided'.

' therein. Opposed to and abovetheseseats are a..

pair of exhaust valve seats vI5 and I6. Adouble ended door closing valve I'l is. adaptedto. alter,- nately engage the seats I5 and I5* anda.. corre- 40 l sponding valve I8 for opening .the doors is adapt-v ed to unseat from the valveseat I6-while being.V seated upon exhaust seats i6. These twoseats I5' and I6 are ported to the atmosphere through 3 ports 5U and 5I respectively shown behind. the" valve stems. a spring urged cam I9, operated by avalvehandle 253 to alternately open the valve seats I5 and II and alternatively. close the exhaust seats; I5v and I6.

Inorder to convey theuid medium fromfthef. control valve I2 to the door closing end oi the" door engine, door closing pipes2l. extend from*v the chamber enclosing the controlvalveseat I 5.: to the pipe couplingt` atthe-doorclosing end off thedoor engine. A four-Way emergency passeur These two valves are controlledby.

the pipes 2l and ports and passages 23, 24 and- 29 of the emergency valve and thence into the right hand end of the door engine while the exhaust medium from the left hand end of the cyl, inder I exhausts through either exhaust port 25,

The cock 21 of this or through the open exhaust seat I6 above the closed valve I8.

A door opening pipe 30 is connected to ther chamber surrounding the valve seat I 6 and to one end of a double acting ball check valve 3I which has a pair of elastic valve seats 32 and 33 in opposite ends thereof. A ball valve 34 is adapted to be moved by the: uid medium to seat on either of the two seats depending upon the pressures existing in the system. The end of the double check valve carrying the seat 33 is connected by an emergency pipe 35 to the port 26 of the emergency valve so that it normally exhausts through the passages 25 and 40 to the atmosphere when the emergency valve is in full line position shown in the drawing. Intermediate the bore of the double check valve housing the ball 34, is a port 3S to which a door opening and emergency pipe 31 is connected, while the other end of this pipe is connected to the coupling I0 of the door opening end of the door engine. The pipes 3 and 31 are jointly considered to be the door opening pipes and thus the double check valve 3I is considered as being in the door opening pipes. The pipes 31 and 35 may be jointly considered the emergency door opening pipes, as when the control valve is in the door closing position and the emergency valve handle 28 is in the dottedl line position shown.

The passage of khuid medium through the system is shown by the arrows, the full line arrows designating the path of the medium for closing the bus doors, the dotted line arrows indicating the course of iiuid medium for opening the bus doors, while the dot and clash arrows indicate the flow of uid pressure for an emergency opening of the bus doors. Thus when the bus is traveling with its doors closed, the pressure of the fluid medium is exercised through the pipe 2l and right hand end of the door engine to move the piston 2 to the left hand end of a door engine, thereby causing the air in the left hand end to exhaust through pipes 31 and 3D into the exhaust port 5I above the valve I5, or these pipes may be of such capacity to house all of the exhaust from the left hand end of the cylinder, or the exhaust may at times be effected through the double acting check valve to the emergency valve for exhausting through the port 25. Should any emergency occur whereby it is desirable for a passenger of the bus to open the doors independently of control by the operator, the passenger has merely to swing the emergency valve handle 28 to dotted line position shown in the drawing which causes passage 30 to communicate the ports 23 and 26 while causing the passage 29 to communicate the ports 24 and to exhaust the right hand end of the door engine to the atmosphere and cut it off from the pressure of the fluid medium coming from the pipe 2|. This switch of the emergency valve causes the fluid medium to then pass from the ,control valve I2 via the pipe 2I and emergency valve 22 into the emergency pipe 35 in the direction o f the dot and dash arrows which causes the ball valve 34 to seat upon the seat 32 thereby directing the fluid medium through pipe 31 in the direction of the dot and dash arrow to pass in to the door opening end of the door engine, thereby moving its piston-2 to the right of the drawing to open the bus doors. Whenever the control valve handle 20 is in the dotted line position shown in the drawing, the valve I8 will be unseated from its seat IB while valve I1 is seated upon its seat I5 thereby permitting the iuid pressure to pass from the reservoir to the door opening pipe 30, thence moving the ball check 34 to its seat 33 tor direct the pressure to the door opening end of the engine through pipe 31, as shown by the dotted line arrows, in which event there is then no occasion for operation of the emergency valve, as the bus doors are already open. As long as the emergency valve is in the position shown in dotted lines in the drawing, no fluid medium can be passed to the door closing end of the door engine by the operation of the control valve as the door closing end of the engine is exhausting through pipe 2| and exhaust port 25. Accordingly, in order for the operator to close the bus doors before moving the bus, it is necessary that he go to the passenger emergency valve adjacent the doors and switch the emergency valve to the full line position before the operator can again manipulate the bus doors from the control station or valve l2.

From the foregoing it is believed that the construction and operation of the system is clear. It will be understood that various changes in the arrangement and relation of parts may be resorted to without departing from the spirit of the invention.

I claim:

1. A bus door operating system comprising a double acting door engine cylinder and piston, a control valve for directing the fluid medium to either end of the door engine cylinder, a door closing conduit connecting the control valve to the door closing end of the engine, an emergency valve in said door closing conduit having passages normally connecting the control valve with the door closing end of the engine, a door opening conduit connecting the controlvalve to the door opening end of the engine, and a double check valve in said door opening conduit having a connection with said emergency valve which is normally cut off from the double check valve but which automatically opens to said emergency valve in the door opening conduit when the emergency valve is operated to open the doors, irrespective of the position of the control valve.

2. A bus door operating system comprising a double acting door engine cylinder and piston, and a control valve, a door opening conduit and a separate door closing conduit leading from said control valve, an emergency valve connected to both conduits and to the door closing end of said engine, and a double acting check valve in said door opening conduit having a door opening pipe leading to the door opening end of the engine, whereby said double acting check valve automatically connects the door closing conduit with the door opening pipe when the emergency valve `switches the iiow of medium from the door closing conduit to the double acting check valve, said double acting check valve normally permitting the ow of uid medium to the door opening pipe from said control valve.

3. A bus door operating system comprising a double acting door engine including a cylinder and piston, a door opening pipe and a door closing pipe, a control valve for directing the iiuid medium to either the door opening or to the door closing pipe, an emergency valve in said door opening pipe, a double acting check valve in said door opening pipe between the control and emergency valves, the intermediate portion of said double acting check valve being connected to the door opening end of the door engine, and said emergency Valve being normally in a position to connect said door closing pipe to the door closing end of said engine and being manually operable to cut off the doorclosing end of the engine and to switch the fluid medium from the door closing pipe back to said double acting check f valve to enter the door opening pipe and end of said door engine, and said emergency valve when in said last named position preventing the iluid medium from entering the door closing pipe and end of the engine.

4. A door operating iiuid motor system comprising a double acting door engine cylinder and piston, a four-way two position control valve having a pair of valves each with inlet and exhaust ports adapted to be alternately operated to open or close the doors, a fluid medium reservoir connected to said control valve to supply either of said inlet ports, separate door opening and door closing conduits from said control valve to opposite ends of said cylinder, a double acting check valve included in said door opening conduit, and a two position emergency valve included in said .door closing conduit and connected to said check valve to shunt luid medium from the door closing conduit to said door opening conduit when said emergency valve is shifted to the door open position, the exhaust medium from said door closing end of the cylinder being vented to the at-v mosphere through said emergency valve.

5. In a door operating fluid motor system, a double acting door engine cylinder and piston, a two position control valve having a pair of valves each with inlet and exhaust ports alternately open, a iluid pressure reservoir connected with said inlet ports of the control valve, a double acting check valve, a manually operated two position emergency valve, a door opening conduit connecting said double acting check valve with one of the valves of said control valve and with the door opening end of said engine, a door closing conduit connecting said emergency valve with the other of said valves of the control valve and with the door closing end of said engine, and an emergency conduit connecting said emergency Valve with said double acting check valve to shunt fluid medium from the door closing end of said engine to the doorvopening end of said door engine when said emergency valve is switched to its door opening position from its normal door closed position, and said emergency valve when in its door closed position, admitting fluid medium from the control valve to the door closing end of said engine While exhaust from the door opening end of the engine passes through the door opening conduit to the open exhaust of said control valve.

6. A bus door operating system comprising a cylinder, a double acting piston therein, a control valve, a double acting check Valve, an emergency valve, a conduit connecting said control valve through said check valve with the door opening end of the cylinder, a conduit connecting said control Valve through said emergency valve with the door closing end of said cylinder and a conduit connectingv said emergency valve with said check valve, saidl last named conduit serving, when the emergency valve is actuated, to divert fluid pressure from said emergency valve into said check valve for opening the door.

JOHN R. ALMOND.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Dfate 1,338,379 Leach Apr. 27, 1920 1,806,669 Campbell May 26, 1931 2,243,937 Almond June 3, 1941 

